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Why can I throw null in Java? [duplicate]
... null is treated as a NullPointerException, but that the act of attempting to throw null itself throws a NullPointerException.
In other words, throw checks that its argument is nonnull, and if it is null, it throws a NullPointerException.
JLS 14.18 specifies this behavior:
If evaluation of t...
Copy folder structure (without files) from one location to another
I want to create a clone of the structure of our multi-terabyte file server. I know that cp --parents can move a file and it's parent structure, but is there any way to copy the directory structure intact?
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How to set the maximum memory usage for JVM?
I want to limit the maximum memory used by the JVM. Note, this is not just the heap, I want to limit the total memory used by this process.
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Truncate all tables in a MySQL database in one command?
Is there a query (command) to truncate all the tables in a database in one operation? I want to know if I can do this with one single query.
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How to access parent Iframe from JavaScript
... have an IFrame, which calls a same domain page.
My problem is that I want to access some information from this parent Iframe from this called page (from JavaScript). How can I access this Iframe?
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Find JavaScript function definition in Chrome
Chrome's Developer Tools rock, but one thing they don't seem to have (that I could find) is a way to find a JavaScript function's definition. This would be super handy for me because I'm working on a site that includes many external JS files. Sure grep solves this but in the browser would be much be...
How To Launch Git Bash from DOS Command Line?
I've got what I'm hoping is a simple question, but I haven't been able to find the answer yet. I would like to launch Git Bash from a DOS batch file. Here is what I tried so far:
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Visual Studio: Multiple post-build commands?
Visual Studio 2008 lets me declare a command and attach it to the post-build event for a project. Like a lot of developers, I use it regularly to xcopy files to the application output directory.
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MySQL error 2006: mysql server has gone away
I'm running a server at my office to process some files and report the results to a remote MySQL server.
28 Answers
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Equivalent of varchar(max) in MySQL?
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The max length of a varchar is subject to the max row size in MySQL, which is 64KB (not counting BLOBs):
VARCHAR(65535)
However, note that the limit is lower if you use a multi-byte character set:
VARCHAR(21844) CHARACTER SET utf8
Here are some examples:
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